How to buy a classic long distance

See if the guy will do a Skype/facetime/whatever video call and go over the car to see if it's worth the trip in person. As far as tying up the sale contingent on anything; how do you plan on enforcing that if it doesn't go your way? I would want to see that the guy who is selling it is also the same guy on the title. Too much crap someone could easily buffalo a distant absent buyer.